### Run Simple Configuration Update Example

Source: https://github.com/outercloud/pyapollo/blob/main/README.md

Execute a simple example script for configuration updates.

```bash
python examples/simple_update_examples.py
```

--------------------------------

### Run Custom Configuration Server Example

Source: https://github.com/outercloud/pyapollo/blob/main/README.md

Execute the example script for using a custom configuration server.

```bash
python examples/custom_config_server_demo.py
```

--------------------------------

### Run Asynchronous Client Custom Configuration Server Example

Source: https://github.com/outercloud/pyapollo/blob/main/README.md

Execute the example script for an asynchronous client with a custom configuration server.

```bash
python examples/async_custom_config_server_demo.py
```

--------------------------------

### Run Configuration Update Examples

Source: https://github.com/outercloud/pyapollo/blob/main/README.en.md

Demonstrates various methods for updating configurations, including detailed, simple, and custom server configurations.

```bash
# Detailed configuration update demonstration
python examples/update_config_demo.py
```

```bash
# Simple configuration update examples
python examples/simple_update_examples.py
```

```bash
# Custom config server examples
python examples/custom_config_server_demo.py
```

```bash
# Async client custom config server examples
python examples/async_custom_config_server_demo.py
```

--------------------------------

### Run Detailed Configuration Update Example

Source: https://github.com/outercloud/pyapollo/blob/main/README.md

Execute the script for a detailed demonstration of configuration updates.

```bash
python examples/update_config_demo.py
```

--------------------------------

### Run Synchronous Client Example

Source: https://github.com/outercloud/pyapollo/blob/main/README.md

Execute the synchronous client demonstration script.

```bash
python examples/sync_demo.py
```

--------------------------------

### Configure .env File for PyApollo

Source: https://github.com/outercloud/pyapollo/blob/main/README.md

Run the .env file configuration example, specifying configuration keys as needed. Ensure a .env file exists in the project root or examples directory.

```bash
# 确保项目根目录有 .env 文件或 examples/test.env 文件
# 使用默认键名
python examples/dotenv_demo.py

# 指定配置键名
python examples/dotenv_demo.py --key your_config_key

# 指定不同的文本配置键和JSON配置键
python examples/dotenv_demo.py --key your_config_key --json-key your_json_key
```

--------------------------------

### Run Asynchronous Client Example

Source: https://github.com/outercloud/pyapollo/blob/main/README.md

Execute the asynchronous client demonstration script.

```bash
python examples/async_demo.py
```

--------------------------------

### Configure Environment Variables for PyApollo

Source: https://github.com/outercloud/pyapollo/blob/main/README.md

Set necessary environment variables before running the environment variable configuration example. This example demonstrates using default and specified configuration keys.

```bash
# 先设置必要的环境变量
export APOLLO_META_SERVER_ADDRESS=http://localhost:8080
export APOLLO_APP_ID=your-app-id

# 运行示例（使用默认键名 sample_key）
python examples/env_demo.py

# 运行示例（指定配置键名）
python examples/env_demo.py --key your_config_key

# 运行示例（指定不同的文本配置键和JSON配置键）
python examples/env_demo.py --key your_config_key --json-key your_json_key
```

--------------------------------

### Install pyapollo via pip

Source: https://github.com/outercloud/pyapollo/blob/main/README.en.md

Install the pyapollo library using pip. Ensure you are using a version greater than or equal to 0.2.0.

```bash
pip install pyapollo-zenkilan
```

--------------------------------

### Example .env file for pyapollo configuration

Source: https://github.com/outercloud/pyapollo/blob/main/README.en.md

Configure pyapollo settings by creating a .env file in your project root. This includes required Apollo server details, application ID, and optional authentication and cluster settings.

```dotenv
# Required Apollo Settings
APOLLO_META_SERVER_ADDRESS=http://localhost:8080
APOLLO_APP_ID=your-app-id

# Authentication Settings
APOLLO_USING_APP_SECRET=true
APOLLO_APP_SECRET=your-app-secret

# Optional Settings
APOLLO_CLUSTER=default
APOLLO_ENV=DEV
APOLLO_NAMESPACES=application,common,database
APOLLO_TIMEOUT=10
APOLLO_CYCLE_TIME=30
```

--------------------------------

### PyApollo Parameter Validation Error Handling

Source: https://github.com/outercloud/pyapollo/blob/main/README.md

Illustrates how PyApollo handles invalid parameters during configuration updates by raising a ValueError. Examples include negative timeouts, empty namespaces, and empty app IDs.

```python
try:
    # 无效参数会抛出 ValueError
    client.update_config(timeout=-1)  # 负数超时
    client.update_config(namespaces=[])  # 空命名空间列表
    client.update_config(app_id="")  # 空应用ID
except ValueError as e:
    print(f"参数验证失败: {e}")
```

--------------------------------

### Initialize Synchronous Apollo Client

Source: https://github.com/outercloud/pyapollo/blob/main/README.en.md

Demonstrates initializing the synchronous ApolloClient with direct parameters for meta server address, app ID, and app secret, or without authentication. It also shows loading from environment variables.

```python
from pyapollo.client import ApolloClient

# Method 1: Direct parameters
meta_server_address = "https://your-apollo/meta-server-address"
app_id="your-apollo-app-id"
app_secret="your-apollo-app-secret"

# Apollo client with authentication
apollo = ApolloClient(
    meta_server_address=meta_server_address,
    app_id=app_id,
    app_secret=app_secret,
)

# Apollo client without authentication
apollo = ApolloClient(
    meta_server_address=meta_server_address,
    app_id=app_id,
)

# Method 2: Load from environment variables or .env file
apollo = ApolloClient()  # Automatically loads from environment or .env file
```

--------------------------------

### Synchronous Apollo Client with Custom Config Server

Source: https://github.com/outercloud/pyapollo/blob/main/README.md

Shows how to initialize a synchronous Apollo client by directly specifying the configuration server host and port, bypassing the meta-server discovery. Also demonstrates runtime switching between custom and meta-server configurations.

```python
from pyapollo.client import ApolloClient

# 直接连接到已知配置服务器，无需元服务器
client = ApolloClient(
    app_id="my-app",
    config_server_host="http://config-server.example.com",
    config_server_port=8080
)

# 运行时切换配置服务器
client.update_config(
    config_server_host="http://backup-config.example.com",
    config_server_port=9090
)

# 切换回使用元服务器发现（需要提供 meta_server_address）
client.update_config(
    meta_server_address="http://meta-server.example.com",
    config_server_host=None,  # 清除自定义配置
    config_server_port=None
)
```

--------------------------------

### Async Apollo Client with Authentication

Source: https://github.com/outercloud/pyapollo/blob/main/README.md

Use this snippet to initialize an asynchronous Apollo client with authentication credentials. It demonstrates fetching JSON and text configurations.

```python
import asyncio
from pyapollo.async_client import AsyncApolloClient


async def main():
    meta_server_address = "https://your-apollo/meta-server-address"
    app_id="your-apollo-app-id"
    app_secret="your-apollo-app-secret"

    # 有鉴权的 Apollo 异步客户端
    async with AsyncApolloClient(
        meta_server_address=meta_server_address,
        app_id=app_id,
        app_secret=app_secret,
    ) as client:
        # 获取 text 格式配置项
        val = await client.get_json_value("json_key")
        print(val)

        # 获取 JSON 格式配置项
        json_val = await client.get_value("text_key")
        print(json_val)

    # 无鉴权的 Apollo 异步客户端
    async with AsyncApolloClient(
        meta_server_address=meta_server_address,
        app_id=app_id,
    ) as client:
        # 获取 text 格式配置项
        val = await client.get_json_value("json_key")
        print(val)

        # 获取 JSON 格式配置项
        json_val = await client.get_value("text_key")
        print(json_val)

    # 使用自定义配置服务器的异步客户端
    async with AsyncApolloClient(
        app_id=app_id,
        config_server_host="http://config-server.example.com",
        config_server_port=8080
    ) as client:
        # 动态更新配置
        await client.update_config(
            timeout=120,
            namespaces=["application", "cache"]
        )

        val = await client.get_value("sample_key")
        print(val)


if __name__ == "__main__":
    asyncio.run(main())
```

--------------------------------

### Fetch Configurations with Synchronous Apollo Client

Source: https://github.com/outercloud/pyapollo/blob/main/README.en.md

Shows how to retrieve configuration values using the synchronous ApolloClient. Supports fetching values in text format and JSON format.

```python
# Get text format configuration
val = apollo.get_value("text_key")
print(val)

# Get JSON format configuration
json_val = apollo.get_json_value("json_key")
print(json_val)
```

--------------------------------

### Initialize and Use Asynchronous Apollo Client

Source: https://github.com/outercloud/pyapollo/blob/main/README.en.md

Illustrates initializing and using the asynchronous AsyncApolloClient within an async context. Supports authentication, no authentication, and custom config server hosts.

```python
import asyncio
from pyapollo.async_client import AsyncApolloClient


async def main():
    meta_server_address = "https://your-apollo/meta-server-address"
    app_id="your-apollo-app-id"
    app_secret="your-apollo-app-secret"

    # Apollo async client with authentication
    async with AsyncApolloClient(
        meta_server_address=meta_server_address,
        app_id=app_id,
        app_secret=app_secret,
    ) as client:
        # Get text format configuration
        val = await client.get_json_value("json_key")
        print(val)

        # Get JSON format configuration
        json_val = await client.get_value("text_key")
        print(json_val)

    # Apollo async client without authentication
    async with AsyncApolloClient(
        meta_server_address=meta_server_address,
        app_id=app_id,
    ) as client:
        # Get text format configuration
        val = await client.get_json_value("json_key")
        print(val)

        # Get JSON format configuration
        json_val = await client.get_value("text_key")
        print(json_val)

    # Async client with custom config server
    async with AsyncApolloClient(
        app_id=app_id,
        config_server_host="http://config-server.example.com",
        config_server_port=8080
    ) as client:
        # Dynamically update configuration
        await client.update_config(
            timeout=120,
            namespaces=["application", "cache"]
        )

        val = await client.get_value("sample_key")
        print(val)


if __name__ == "__main__":
    asyncio.run(main())
```

--------------------------------

### Connect Directly to Custom Config Server

Source: https://github.com/outercloud/pyapollo/blob/main/README.en.md

Initialize the ApolloClient by directly specifying the `config_server_host` and `config_server_port` to bypass meta server discovery. You can also switch to a custom config server or back to meta server discovery at runtime.

```python
from pyapollo.client import ApolloClient

# Connect directly to known config server, no meta server needed
client = ApolloClient(
    app_id="my-app",
    config_server_host="http://config-server.example.com",
    config_server_port=8080
)

# Switch config server at runtime
client.update_config(
    config_server_host="http://backup-config.example.com",
    config_server_port=9090
)

# Switch back to meta server discovery (need to provide meta_server_address)
client.update_config(
    meta_server_address="http://meta-server.example.com",
    config_server_host=None,  # Clear custom config
    config_server_port=None
)
```

--------------------------------

### Synchronous Apollo Client Dynamic Configuration Updates

Source: https://github.com/outercloud/pyapollo/blob/main/README.md

Demonstrates how to dynamically update configuration parameters for a synchronous Apollo client without re-instantiating it. Covers updating single/multiple parameters, namespaces, authentication, and custom servers.

```python
from pyapollo.client import ApolloClient

# 创建客户端
client = ApolloClient(
    meta_server_address="http://localhost:8080",
    app_id="my-app",
    timeout=30,
    cycle_time=60
)

# 动态更新单个参数
client.update_config(timeout=120)

# 批量更新多个参数
client.update_config(
    timeout=60,
    cycle_time=30,
    cluster="production"
)

# 更新命名空间
client.update_config(
    namespaces=["application", "redis", "database"]
)

# 环境切换
client.update_config(
    meta_server_address="http://prod-apollo:8080",
    env="PROD",
    cluster="production"
)

# 添加认证
client.update_config(
    app_secret="your-secret-key"
)

# 自定义配置服务器（绕过元服务器发现）
client.update_config(
    config_server_host="http://config.example.com",
    config_server_port=8080
)

# 查看当前配置
config = client.get_current_config()
print(config)
```

--------------------------------

### Configure PyApollo with Environment Variables

Source: https://github.com/outercloud/pyapollo/blob/main/README.en.md

Set environment variables for APOLLO_META_SERVER_ADDRESS and APOLLO_APP_ID, then run the environment variable demonstration script. Supports specifying configuration keys.

```bash
# First set the required environment variables
export APOLLO_META_SERVER_ADDRESS=http://localhost:8080
export APOLLO_APP_ID=your-app-id

# Run the example (with default key name 'sample_key')
python examples/env_demo.py

# Run the example (with specified configuration key)
python examples/env_demo.py --key your_config_key

# Run the example (with different text and JSON configuration keys)
python examples/env_demo.py --key your_config_key --json-key your_json_key
```

--------------------------------

### Configure PyApollo with .env File

Source: https://github.com/outercloud/pyapollo/blob/main/README.en.md

Use a .env file for configuration. The script supports specifying configuration keys for text and JSON values.

```bash
# Make sure you have a .env file in the project root or examples/test.env
# Using default key names
python examples/dotenv_demo.py

# Specify configuration key
python examples/dotenv_demo.py --key your_config_key

# Specify different text and JSON configuration keys
python examples/dotenv_demo.py --key your_config_key --json-key your_json_key
```

--------------------------------

### Configure pyapollo using a custom .env file path

Source: https://github.com/outercloud/pyapollo/blob/main/README.en.md

Load Apollo client settings from a custom .env file path using ApolloSettingsConfig. This allows for flexible configuration management.

```python
from pyapollo.settings import ApolloSettingsConfig
from pyapollo.client import ApolloClient

# Load from custom .env file path
settings = ApolloSettingsConfig.from_env_file("path/to/custom.env")
client = ApolloClient(settings=settings)
```

--------------------------------

### Set pyapollo configuration using environment variables

Source: https://github.com/outercloud/pyapollo/blob/main/README.en.md

Configure pyapollo by exporting environment variables. This method is useful for deployment environments where direct file manipulation is not preferred.

```bash
# Required settings
export APOLLO_META_SERVER_ADDRESS=http://localhost:8080
export APOLLO_APP_ID=your-app-id

# Authentication settings (optional)
export APOLLO_USING_APP_SECRET=true
export APOLLO_APP_SECRET=your-app-secret

# Other optional settings
export APOLLO_CLUSTER=default
export APOLLO_ENV=DEV
export APOLLO_NAMESPACES=application,common,database
export APOLLO_TIMEOUT=10
export APOLLO_CYCLE_TIME=30
```

--------------------------------

### Configure pyapollo using ApolloSettingsConfig object

Source: https://github.com/outercloud/pyapollo/blob/main/README.en.md

Instantiate ApolloSettingsConfig with direct parameters and pass it to the ApolloClient. This provides a programmatic way to configure the client.

```python
from pyapollo.settings import ApolloSettingsConfig
from pyapollo.client import ApolloClient

# Create settings object
settings = ApolloSettingsConfig(
    meta_server_address="http://localhost:8080",
    app_id="your-app-id",
    using_app_secret=True,
    app_secret="your-app-secret"
)

# Pass settings to client
client = ApolloClient(settings=settings)
```

--------------------------------

### Add pyapollo to requirements.txt

Source: https://github.com/outercloud/pyapollo/blob/main/README.en.md

Include pyapollo in your project's requirements.txt file for dependency management. Specify a version of 0.2.0 or higher.

```text
pyapollo-zenkilan>=0.2.0
```

--------------------------------

### Handle Parameter Validation Errors

Source: https://github.com/outercloud/pyapollo/blob/main/README.en.md

The `update_config` method performs parameter validation and raises a `ValueError` for invalid inputs. Ensure parameters like timeout, namespaces, and app_id meet the required criteria.

```python
try:
    # Invalid parameters will raise ValueError
    client.update_config(timeout=-1)  # Negative timeout
    client.update_config(namespaces=[])  # Empty namespace list
    client.update_config(app_id="")  # Empty app ID
except ValueError as e:
    print(f"Parameter validation failed: {e}")
```

--------------------------------

### Update pyapollo Client Configuration Dynamically

Source: https://github.com/outercloud/pyapollo/blob/main/README.en.md

Use `update_config` to modify single or multiple client parameters at runtime. This method supports updating timeouts, namespaces, environment settings, authentication, and custom config server addresses.

```python
from pyapollo.client import ApolloClient

# Create client
client = ApolloClient(
    meta_server_address="http://localhost:8080",
    app_id="my-app",
    timeout=30,
    cycle_time=60
)

# Update single parameter
client.update_config(timeout=120)

# Batch update multiple parameters
client.update_config(
    timeout=60,
    cycle_time=30,
    cluster="production"
)

# Update namespaces
client.update_config(
    namespaces=["application", "redis", "database"]
)

# Environment switching
client.update_config(
    meta_server_address="http://prod-apollo:8080",
    env="PROD",
    cluster="production"
)

# Add authentication
client.update_config(
    app_secret="your-secret-key"
)

# Custom config server (bypass meta server discovery)
client.update_config(
    config_server_host="http://config.example.com",
    config_server_port=8080
)

# View current configuration
config = client.get_current_config()
print(config)
```

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